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    <title>Document</title>
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<script>
    var arr1 = [1, 2, 3, 4, 5];
    //（1）@@@从数组最后删除，注意括号内传参没用。(不可传参)
    var jieguo2 = arr1.pop();
    console.log(arr1); //[10, 20, 30, 1, 2, 3, 4, 5, 1]//原数组改变,但是只删除一个
    console.log(jieguo2); //2//@@@返回的是删除的元素值
</script>

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